In the article, the looks into different possibilities of social integration of people, social groups, pointing to the cause of marginalization – the low level of culture, communication capacity, selfknowledge. Regardless of the social status of the person: poor, employed, unemployed or immigrant, social inclusion is stimulated by the individual’s interest in knowing, acting, and manifesting himself. Social integration can and must be stimulated by state institutions, as well. Otherwise, dissatisfaction among the marginalized will lead to destabilization of the political system and social conflicts. The social integration of immigrants is a way of mitigating the social crisis that has occurred in European countries. The key objectives of the investigation are: to analyze the challenges to the security and instability of the political system of the European States; to define social integration and inclusion as a factor of the dynamic stability of the political system; to interpret marginalization as a destabilizing factor; to analyze the social integration of immigrants through knowledge and communication.